Container

ABSTRACT

A vessel is configured to hold a product in an interior region formed in the vessel. In illustrative embodiments, the vessel includes a floor and a sidewall coupled to the floor to extend away from the floor. Together the floor and sidewall cooperate to define the interior region. A vessel in accordance with the present disclosure is configured to hold a product in an interior region. In illustrative embodiments, the vessel is an insulated container such as a drink cup. In illustrative embodiments, the vessel is a container such as a shampoo bottle.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a U.S. nationalization under 35 U.S.C. §371 ofInternational Application No. PCT/US2014/027551, filed Mar. 14, 2014,which claims priority to U.S. Provisional Application No. 61/783,994,filed Mar. 14, 2013.

BACKGROUND

The present disclosure relates to vessels, and in particular to cup orbottles. More particularly, the present disclosure relates to a cupformed from polymeric materials.

SUMMARY

A vessel in accordance with the present disclosure is configured to holda product in an interior region. In illustrative embodiments, the vesselis an insulated container such as a drink cup. In illustrativeembodiments, the vessel is a container such as a shampoo bottle.

In illustrative embodiments, a container is formed multi-layer tube in amulti-layer co-extrusion blow molding process. The multi-layer tubeincludes an inner polymeric layer, an outer polymeric spaced apart fromthe inner polymeric material, and a middle cellular non-aromaticpolymeric material located between the inner and outer polymeric layers.

In illustrative embodiments, the middle cellular non-aromatic polymericlayer has a density in a range of about 0.01 g/cm³ to about 0.19 g/cm³.In illustrative embodiments, the middle cellular non-aromatic polymericlayer has a density in a range of about 0.05 g/cm³ to about 0.19 g/cm³.In illustrative embodiments, the middle cellular non-aromatic polymericlayer has a density in a range of about 0.1 g/cm³ to about 0.185 g/cm³.

In a further embodiment, a vessel comprises a floor and a sidewall. Aside wall is coupled to the floor and arranged to extend upwardly fromground underlying the floor. The side wall and the floor cooperate todefine an interior product-storage region therebetween.

In a further embodiment, the floor and the side wall cooperate to form amonolithic element comprising an inner polymeric layer forming aboundary of the interior product-storage region, an outer polymericlayer arranged to lie in spaced-apart relation to the inner polymericlayer to define a core chamber therebetween, and a middle cellularnon-aromatic polymeric material located in the core chamber to liebetween the outer polymeric layer and the inner polymeric layer.

In a further embodiment, the middle cellular non-aromatic polymericmaterial has a density in a range of about 0.01 g/cm³ to about 0.19g/cm³.

In a further embodiment, the middle cellular non-aromatic polymericmaterial comprises polypropylene.

In a further embodiment, the density of the middle cellular non-aromaticpolymeric material is in a range of about 0.1 g/cm³ to about 0.185g/cm³.

In a further embodiment, each of the inner polymeric layer, the outerpolymeric layer comprise polypropylene.

In a further embodiment, each of the inner polymeric layer, the outerpolymeric layer comprise polypropylene.

In a further embodiment, the middle cellular non-aromatic polymericmaterial comprises high-density polyethylene.

In a further embodiment, the density of the middle cellular non-aromaticpolymeric material is in a range of about 0.1 g/cm³ to about 0.185g/cm³.

In a further embodiment, each of the inner polymeric layer, the outerpolymeric layer comprise polypropylene.

In a further embodiment, the density of the middle cellular non-aromaticpolymeric material is in a range of about 0.1 g/cm³ to about 0.185g/cm³.

In a further embodiment, each of the inner polymeric layer, the outerpolymeric layer, and the middle cellular non-aromatic polymeric materialcomprises polypropylene.

In a further embodiment, the vessel further comprises a brim coupled toan upper portion of the side wall and formed to include a mouth openinginto the interior product-storage region.

In a further embodiment, the brim is coupled to each of the innerpolymeric layer and the outer polymeric layer to close an annularopening into a portion of the core chamber formed in the side wall.

In a further embodiment, the middle cellular non-aromatic polymericmaterial is the only material located in the core chamber.

In a further embodiment, the middle cellular non-aromatic polymericmaterial is arranged to fill the core chamber completely.

In a further embodiment, the middle cellular non-aromatic polymericmaterial comprises polypropylene.

In a further embodiment, the density of the middle cellular non-aromaticpolymeric material is in a range of about 0.1 g/cm³ to about 0.185g/cm³.

In a further embodiment, each of the inner polymeric layer, the outerpolymeric layer comprise polypropylene.

In a further embodiment, a vessel comprises a floor and a side wall. Theside wall is coupled to the floor and arranged to extend upwardly fromground underlying the floor. The side wall cooperates with the floor todefine an interior product-storage region therebetween.

In a further embodiment, the floor and the side wall cooperate to form amonolithic element comprising an inner polymeric layer forming aboundary of the interior product-storage region, an outer polymericlayer arranged to lie in spaced-apart relation to the inner polymericlayer to define a core chamber therebetween, and a middle cellularnon-aromatic polymeric material located in the core chamber to liebetween the outer polymeric layer and the inner polymeric layer.

In a further embodiment, the inner polymeric layer, the outer polymericlayer, and a middle cellular non-aromatic polymeric material cooperateto provide means for maximizing a compressive strength of the vessel astested by top-load testing and a shear strength of the vessel as testedby side-wall rigidity testing while minimizing a weight of the vessel.

In a further embodiment, the middle cellular non-aromatic polymericmaterial comprises polypropylene.

In a further embodiment, the density of the middle cellular non-aromaticpolymeric material is in a range of about 0.1 g/cm³ to about 0.185g/cm³.

In a further embodiment, the vessel has an average density in a densityrange of about 0.51 g/cm³ to about 0.91 g/cm³.

In a further embodiment, the compression strength of the vessel isgreater than a compression strength of a control vessel having a massabout the same as a mass of the vessel and a shape about the same as ashape of the vessel.

In a further embodiment, the compression strength of the vessel is about5% to about 30% greater than the compression strength of the controlvessel.

In a further embodiment, the shear strength of the vessel is greaterthan a shear strength of a control vessel having a mass about the sameas a mass of the vessel and a shape about the same as a shape of thevessel.

In a further embodiment, the compression strength of the vessel is about3% to about 30% greater the compression strength of the control vessel.

In a further embodiment, the average density is about 0.91 g/cm³.

In a further embodiment, the compression strength of the vessel is about9% greater than a compression strength of a control vessel having a massabout the same as a mass of the vessel a shape about the same as a shapeof the vessel.

In a further embodiment, the shear strength of the vessel is about 4%greater than a shear strength of a control vessel having a mass aboutthe same as a mass of the vessel and a shape about the same as a shapeof the vessel.

In a further embodiment, the density range is about 0.6 g/cm³ to about0.8 g/cm³.

In a further embodiment, the average density is about 0.61 g/cm³.

In a further embodiment, the compression strength of the vessel is about15% greater than a compression strength of a control vessel having amass about the same as a mass of the vessel a shape about the same as ashape of the vessel.

In a further embodiment, the shear strength of the vessel is about 15%greater than a shear strength of a control vessel having a mass aboutthe same as a mass of the vessel and a shape about the same as a shapeof the vessel.

In a further embodiment, the average density is about 0.71 g/cm³.

In a further embodiment, the compression strength of the vessel is about26% greater than a compression strength of a control vessel having amass about the same as a mass of the vessel and a shape about the sameas a shape of the vessel.

In a further embodiment, the shear strength of the vessel is about 24%greater than a shear strength of a control vessel having a mass aboutthe same as a mass of the vessel and a shape about the same as a shapeof the vessel.

In a further embodiment, the shear strength of the vessel is about 24%greater than a shear strength of a control vessel having a mass aboutthe same as a mass of the vessel and a shape about the same as a shapeof the vessel.

In a further embodiment, the vessel has a mass of about 56 grams.

Additional features of the present disclosure will become apparent tothose skilled in the art upon consideration of illustrative embodimentsexemplifying the best mode of carrying out the disclosure as presentlyperceived.

BRIEF DESCRIPTIONS OF THE DRAWINGS

The detailed description particularly refers to the accompanying figuresin which:

FIG. 1 is a perspective view of a first embodiment of a container inaccordance with the present disclosure showing that the containerincludes, from top to bottom, a brim, a side wall, and a floor, andsuggesting that the container is formed from a multilayer tube accordingto a container-manufacturing process as suggested in FIGS. 3A-4;

FIG. 2 is an enlarged sectional view of a portion of a side wallincluded in the container of FIG. 1 showing that the side wall is madeform a multilayer tube that includes, from left to right, an outerpolymeric layer, a middle cellular non-aromatic polymeric layer, and aninner polymeric layer;

FIGS. 3A-3C are a series of partial perspective view of a firstembodiment of a container-manufacturing process in accordance with thepresent disclosure showing the formation of the container of FIG. 1;

FIG. 3A is a partial perspective view of a portion of thecontainer-manufacturing process showing that the container-manufacturingprocess begins with extruding an inner layer, a middle layer, and anouter layer to establish a multi-layer tube that is received between twomold halves for forming as suggested in FIG. 3B;

FIG. 3B is a view similar to FIG. 3A showing the two mold halves in aclosed position trapping the multilayer tube therebetween in a moldcavity formed by the two mold have when the two mold have are closed;

FIG. 3C is a view similar to FIG. 3B showing the two mold halves in anopened position and a molded vessel being ejected from the mold halvesfor further processing to establish the container of FIG. 1 as suggestedin FIG. 4;

FIG. 4 is a diagrammatic view of the container-manufacturing process ofFIGS. 3A-3C showing that the container-manufacturing process includesthe operations extruding the inner layer that provides the innerpolymeric layer, extruding the middle layer that provides the middleinsulative cellular non-aromatic polymeric layer, extruding the outerlayer that provides the outer polymeric layer, establishing a pre-formmultilayer tube, extruding the pre-form multilayer tube into an openmold cavity, closing the mold, pumping air into the pre-form multilayertube in the mold cavity to cause the multi-layer tube to expand and takethe shape of the mold cavity, opening the mold, removing the vessel fromthe mold cavity, cutting a top portion off the vessel to establish abody as suggested in FIG. 5, and forming the container of FIG. 1 fromthe body;

FIG. 5 is a view similar to FIG. 1 showing the body formed during thecontainer-manufacturing process of FIG. 4;

FIG. 6 is a perspective view taken from a bottom of the body showing afloor included in the container;

FIGS. 7A-7D are a series of partial perspective view of a secondembodiment of a container-manufacturing process in accordance with thepresent disclosure showing the formation a body as suggested in FIG. 9that processed to form a container;

FIG. 7A is a partial perspective view of a portion of thecontainer-manufacturing process showing that the container-manufacturingprocess begins with extruding an inner layer, a middle layer, and anouter layer to establish a multi-layer tube that is received between twomold halves for forming as suggested in FIG. 7B;

FIG. 7B is a view similar to FIG. 7A showing the two mold halves in aclosed position trapping the multilayer tube therebetween in a moldcavity formed by the two mold have when the two mold have are closed;

FIG. 7C is a view similar to FIG. 7B showing the two mold halves in anopened position and a molded vessel being ejected from the mold halvesfor further processing where a cutting operation removes a top andbottom end of the vessel to establish a side wall;

FIG. 7D is a view similar to FIG. 7C showing the side wall after thecutting operation has been performed and a floor has been coupled to abottom end of the side wall to establish a body as suggested in FIG. 9;

FIG. 8 is a diagrammatic view of the container-manufacturing process ofFIGS. 7A-7D showing that the container-manufacturing process includesthe operations extruding the inner layer that provides the innerpolymeric layer, extruding the middle layer that provides the middleinsulative cellular non-aromatic polymeric layer, extruding the outerlayer that provides the outer polymeric layer, establishing a pre-formmultilayer tube, extruding the pre-form multilayer tube into an openmold cavity, closing the mold, pumping air into the pre-form multilayertube in the mold cavity to cause the multi-layer tube to expand and takethe shape of the mold cavity, opening the mold, removing the vessel fromthe mold cavity, cutting top and bottom portions off the vessel toestablish the side wall, forming the floor, coupling the floor to theside wall to establish the body, and forming the container as suggestedin FIG. 9;

FIG. 9 is a perspective view of a another embodiment of the body formedusing the container-manufacturing process of FIGS. 7A-8 with portionsbroken away to reveal that the container includes the side wall and thefloor;

FIG. 10 is a perspective view taken from a bottom of the body of FIG. 9showing the floor coupled to the side wall of the body;

FIG. 11 is a perspective view of another embodiment of a container inaccordance with the present disclosure suggesting that a containerincluding, from top to bottom, a brim, a side wall including a pluralityof ribs, and a floor may be formed using the container-manufacturingprocesses of the present disclosure;

FIG. 12 is a perspective view taken from a bottom of the container ofFIG. 11 showing the floor appended to the side wall of the container

FIG. 13A is a photograph showing two containers in accordance withanother embodiment of the present disclosure;

FIG. 13B is a photograph showing one of the containers of FIG. 13A witha portion of a side wall removed for photographing as suggested in FIG.13C;

FIG. 13C is an enlarged photograph of a portion of the side wall of FIG.13B showing that the side wall includes, from top bottom, a innerpolymeric layer, a middle insulative cellular non-aromatic polymericlayer, an outer polymeric layer;

FIG. 13D is an enlarged photograph of a portion of the side wall insection showing that the side wall includes, from top to bottom, anouter polymeric layer (outside skin), a middle insulative cellularnon-aromatic polymeric layer (foam core), and an inner polymeric layer(inside skin);

FIG. 13E is a photograph showing one of the containers of FIG. 13Acoupled to a top-load testing device undergoing top-load testing;

FIG. 14A is a photograph showing another embodiment of a container inaccordance with the present disclosure being removed from a mold cavityafter air has been pumped into a pre-form multilayer tube in a moldcavity to cause the multi-layer tube to expand and take the shape of themold cavity;

FIG. 14B is a photograph showing a series of finished containers formedin accordance with the present disclosure;

FIG. 14C is an enlarged photograph showing a section of a side wallincluded in the containers of FIGS. 14A and 14B showing that the sidewall includes, from top bottom, a inner polymeric layer, a middleinsulative cellular non-aromatic polymeric layer, and an outer polymericlayer;

FIG. 14D is a photograph showing two containers formed in accordancewith the present disclosure and two multi-layer tubes used to form thecontainers;

FIG. 14E is a photograph showing two containers formed in accordancewith the present disclosure and two multi-layer tubes used to form thecontainers;

FIG. 15 is a perspective view of another embodiment of a containerformed in accordance with the present disclosure and subjected to bothside-wall rigidity testing as suggested in FIGS. 16 and 17 and top-loadtesting;

FIG. 16 is a photograph of a side-wall rigidity testing apparatus usedto test side-wall rigidity of various containers, the photograph showingan illustrative container located between a stationary Y-bar and amovable T-bar used to deform the side wall of the container;

FIG. 17 is a view similar to FIG. 16 showing that the side-wall rigiditytesting apparatus includes a force gauge coupled to the T-bar to measureforce applied to the side wall of the container and a travel gaugecoupled to the force gauge to measure a distance the side wall has beendeformed;

FIG. 18 is a graph showing results of top-load testing for variouscontainers having different densities and different constructions butall the containers having a similar weight of about 56 grams;

FIG. 19 is a graph showing results of sidewall-rigidity testing forvarious containers having different densities and differentconstructions but all the containers having a similar weight of about 56grams;

FIG. 20 is a graph showing results of top-load testing for variouscontainers having different densities and different constructions butall the containers having a similar wall thickness of about 0.039inches;

FIG. 21 is a graph showing results of sidewall-rigidity testing forvarious containers having different densities and differentconstructions but all the containers having a similar wall thickness ofabout 0.039 inches; and

FIG. 22 is a diagrammatic view of another embodiment of a vessel madeusing a multi-layer tube including an inner polymeric layer, and outerpolymeric layer, and a middle insulative cellular non-aromatic polymericlayer therebetween and showing that the vessel has been sectionedthrough an X-Y plane so as to identify reference radius r_(o) and r_(i)which may be used to calculate a moment area of inertia for the vessel.

DETAILED DESCRIPTION

A first embodiment of a container 10 in accordance with the presentdisclosure is shown in FIG. 1. Container 10 is made from a multi-layertube 12, also called multi-layer parison 12, as shown in FIGS. 3A-3C and7A-7C. Multi-layer tube 12 includes an inner polymeric layer 12I, amiddle cellular non-aromatic polymeric layer 12M, and an outer polymericlayer 12O as shown in FIG. 2. Container 10 is formed using a firstembodiment of a container-manufacturing process 100 as shown, forexample, in FIGS. 3A-4. Another embodiment of a body 218 in accordancewith the present disclosure is shown, for example in FIGS. 9 and 10.Body 218 is formed during and used in a second embodiment of acontainer-manufacturing process 300 as shown, for example, in FIGS.7A-8. Still yet another embodiment of a container 410 formed using oneof the container-manufacturing process of the present disclosure isshown, for example, in FIGS. 11 and 12. Another embodiment of acontainer 510 formed using one of the container-manufacturing processesof the present disclosure is shown, for example, in FIGS. 13A and 13E.Another embodiment of a container 610 is formed using one of thecontainer-manufacturing processes of the present disclosure is shown,for example, in FIGS. 14B, 14D, and 14E. Still yet another embodiment ofa container 710 is formed using the container-manufacturing processes ofthe present disclosure and is shown in FIG. 15. Container 710 issubjected to both side-wall rigidity testing and top-loading testing invarious configurations as show in FIGS. 18-21.

Container 10 is made during container-manufacturing process 100 frommulti-layer tube 12 as shown in FIG. 3A-3C. Multi-layer tube 12 includesinner polymeric layer 12I, middle cellular non-aromatic polymeric layer12M, and outer polymeric layer 12O as shown in FIG. 2. In one example,inner polymeric layer 12I, middle insulative cellular non-aromaticpolymeric layer 12M, and outer polymeric layer 12O are made from thesame polymeric material or materials. In another example, each of theinner polymeric layer 12I, middle insulative cellular non-aromaticpolymeric layer 12M, and outer polymeric layer 12O are made fromdifferent materials.

In one example, inner and outer polymeric layers 12I, 12O are made frompolypropylene. In another example, inner and outer polymeric layers 12I,12O are made from high density polyethylene. In still yet anotherexample, one of the polymeric layers may include a polymeric materialand an oxygen barrier material such as Ethylene Vinyl Alcohol (EVOH).However, inner and outer polymeric layers 12I, 12 may be made from anysuitable polymeric material.

Middle insulative cellular non-aromatic polymeric layer 12M isconfigured to provide means for insulating a beverage or food placed inan interior region 14 formed in container 10, forming a structure havingsufficient mechanical characteristics to support the beverage or food,and providing resistance to deformation and puncture. In one example,middle insulative cellular non-aromatic polymeric layer 12M is made froman insulative cellular non-aromatic high density polyethylene material.In another example, middle insulative cellular non-aromatic polymericlayer 12M is made from a predominantly polypropylene material. Referenceis hereby made to U.S. application Ser. No. 13/491,007, filed Jun. 7,2012 and titled POLYMERIC MATERIAL FOR AN INSULATED CONTAINER and toU.S. application Ser. No. 14/063,252, filed May 1, 2014 and titledPOLYMERIC MATERIAL FOR AN INSULATED CONTAINER, for disclosure relatingto a formulation used to make polypropylene based insulative cellularnon-aromatic polymeric material, which application is herebyincorporated in its entirety herein.

In one exemplary embodiment, a formulation used to produce the cellularpolymeric material includes at least one polymeric material. Thepolymeric material may include one or more base resins. In one example,the base resin is polypropylene. In an illustrative embodiment, a baseresin can include Borealis WB140 HMS polypropylene homopolymer. Inanother illustrative embodiment, a base resin can include Braskem F020HCpolypropylene homopolymer. In an embodiment, a base resin can includeboth Borealis WB140 HMS polypropylene homopolymer and Braskem F020HCpolypropylene homopolymer.

In embodiments with more than one polypropylene copolymer base resin,different polypropylene copolymers can be used depending on theattributes desired in the formulation. Depending on the desiredcharacteristics, the ratio of two polypropylene resins may be varied,e.g., 10%/90%, 20%/80%, 25%/75%, 30%/70%, 35%/65%, 40%/60%, 45%/55%,50%/50%, etc. In an embodiment, a formulation includes threepolypropylene resins in the base resin. Again, depending on the desiredcharacteristics, the percentage of three polypropylene resins can bevaried, 33%/33%/33%, 30%/30%/40%, 25%/25%/50%, etc.

In illustrative embodiments, a polymeric material includes a primarybase resin. In illustrative embodiments, a base resin may polypropylene.In illustrative embodiments, an insulative cellular non-aromaticpolymeric material comprises a polypropylene base resin having a highmelt strength, a polypropylene copolymer or homopolymer (or both). In anembodiment, a formulation of the polymeric material comprises about 50wt % to about 100 wt %, about 70 wt % to about 100 wt %, about 50 wt %to about 99 wt %, 50 wt % to about 95 wt %, about 50 wt % to about 85 wt%, about 55 wt % to about 85 wt %, about 80 wt % to about 85 wt %, about80 wt % to about 90 wt %, about 80 wt % to about 91 wt %, about 80 wt %to about 92 wt %, about 80 wt % to about 93 wt %, about 80 wt % to about94 wt %, about 80 wt % to about 95 wt %, about 80 wt % to about 96 wt %,about 80 wt % to about 97 wt %, about 80 wt % to about 98 wt %, about 80wt % to about 99 wt %, about 85 wt % to about 90 wt %, or about 85 wt %to about 95 wt % of the primary base resin. In an embodiment, a colorantcan be about 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%,92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100%.

As defined hereinbefore, any suitable primary base resin may be used.One illustrative example of a suitable polypropylene base resin isDAPLOY™ WB140 homopolymer (available from Borealis A/S) which is a highmelt strength structural isomeric modified polypropylene homopolymer.

In illustrative embodiments, a polymeric material includes a secondaryresin, wherein the secondary resin can be a polypropylene copolymer orhomopolymer (or both). In another embodiment, a secondary resin can beabout 0 wt % to about 50 wt %, about 0 wt % to about 30 wt %, about 0 wt% to about 25 wt %, about 0 wt % to about 20 wt %, about 0 wt % to about15 wt %, about 10 wt % to about 50 wt %, about 10 wt % to about 40 wt %,about 10 wt % to about 30 wt %, about 10 wt % to about 25 wt %, about 10wt % to about 20 wt %, or about 10 wt % to about 15 wt % of a secondaryresin. In an embodiment, a polymeric material includes about 0 wt %,about 10 wt %, about 15 wt %, about 20 wt %, about 25 wt %, or about 30wt %. In an embodiment, a polymeric material does not have a secondaryresin. In a particular embodiment, a secondary resin can be a highcrystalline polypropylene homopolymer, such as F020HC (available fromBraskem) or PP 527K (available from Sabic). In an embodiment, apolymeric material lacks a secondary resin.

Nucleating agent means a chemical or physical material that providessites for cells to form in a molten formulation mixture. Nucleatingagents may include chemical nucleating agents and physical nucleatingagents. The nucleating agent may be blended with the formulation that isintroduced into the hopper of the extruder. Alternatively, thenucleating agent may be added to the molten resin mixture in theextruder.

Suitable physical nucleating agents have desirable particle size, aspectratio, and top-cut properties. Examples include, but are not limited to,talc, CaCO₃, mica, and mixtures of at least two of the foregoing. Onerepresentative example is Heritage Plastics HT6000 Linear Low DensityPolyethylene (LLDPE) Based Talc Concentrate.

Suitable chemical nucleating agents decompose to create cells in themolten formulation when a chemical reaction temperature is reached.These small cells act as nucleation sites for larger cell growth from aphysical or other type of blowing agent. In one example, the chemicalnucleating agent is citric acid or a citric acid-based material. Onerepresentative example is HYDROCEROL™ CF-40E (available from ClariantCorporation), which contains citric acid and a crystal nucleating agent.

A “blowing agent” refers to a physical or a chemical blowing agent (orcombination of materials) that acts to expand nucleation sites. Blowingagents may include only chemical blowing agents, only physical blowingagents, combinations thereof, or several types of chemical and physicalblowing agents. The blowing agent acts to reduce density by formingcells in the molten formulation at the nucleation sites. The blowingagent may be added to the molten resin mixture in the extruder.

Chemical blowing agents are materials that degrade or react to produce agas. Chemical blowing agents may be endothermic or exothermic. Chemicalblowing agents typically degrade at a certain temperature to decomposeand release gas. One example of a chemical blowing agent is citric acidor citric-based material. One representative example is HYDROCEROL™CF-40E (available from Clariant Corporation), which contains citric acidand a crystal nucleating agent. Here, the citric acid decomposes at theappropriate temperature in the molten formulation and forms a gas whichmigrates toward the nucleation sites and grows cells in the moltenformulation. If sufficient chemical blowing agent is present, thechemical blowing agent may act as both the nucleating agent and theblowing agent.

In another example, chemical blowing agents may be selected from thegroup consisting of azodicarbonamide; azodiisobutyro-nitrile;benzenesulfonhydrazide; 4,4-oxybenzene sulfonylsemicarbazide; p-toluenesulfonyl semi-carbazide; barium azodicarboxylate;N,N′-dimethyl-N,N′-dinitrosoterephthalamide; trihydrazino triazine;methane; ethane; propane; n-butane; isobutane; n-pentane; isopentane;neopentane; methyl fluoride; perfluoromethane; ethyl fluoride;1,1-difluoroethane; 1,1,1-trifluoroethane; 1,1,1,2-tetrafluoro-ethane;pentafluoroethane; perfluoroethane; 2,2-difluoropropane;1,1,1-trifluoropropane; perfluoropropane; perfluorobutane;perfluorocyclobutane; methyl chloride; methylene chloride; ethylchloride; 1,1,1-trichloroethane; 1,1-dichloro-1-fluoroethane;1-chloro-1,1-difluoroethane; 1,1-dichloro-2,2,2-trifluoroethane;1-chloro-1,2,2,2-tetrafluoroethane; trichloromonofluoromethane;dichlorodifluoromethane; trichlorotrifluoroethane;dichlorotetrafluoroethane; chloroheptafluoropropane;dichlorohexafluoropropane; methanol; ethanol; n-propanol; isopropanol;sodium bicarbonate; sodium carbonate; ammonium bicarbonate; ammoniumcarbonate; ammonium nitrite;N,N′-dimethyl-N,N′-dinitrosoterephthalamide;N,N′-dinitrosopentamethylene tetramine; azodicarbonamide;azobisisobutylonitrile; azocyclohexylnitrile; azodiaminobenzene;bariumazodicarboxylate; benzene sulfonyl hydrazide; toluene sulfonylhydrazide; p,p′-oxybis(benzene sulfonyl hydrazide); diphenylsulfone-3,3′-disulfonyl hydrazide; calcium azide; 4,4′-diphenyldisulfonyl azide; p-toluene sulfonyl azide; and combinations thereof.

In an illustrative embodiment, a nucleating agent can be about 0.1% toabout 20% (w/w), about 0.25% to about 20%, about 0.5% to about 20%,about 0.75% to about 20%, about 1% to about 20%, about 1.5% to about20%, about 2% to about 20%, about 2.5% to about 20%, about 3% to about20%, about 3% to about 20%, about 4% to about 20%, about 4.5% to about20%, about 5% to about 20%, about 0.1% to about 10%, about 0.25% toabout 10%, about 0.5% to about 10%, about 0.75% to about 10%, about 1.0%to about 10%, about 1.5% to about 10%, about 1.0% to about 10%, about2.0% to about 10%, about 2.5% to about 10%, about 3.0% to about 10%,about 3.5% to about 10%, about 4.0% to about 10%, about 4.5% to about10%, about 5.0% to about 10%, about 0.1% to about 5%, about 0.25% toabout 5%, about 0.5% to about 5%, about 0.75% to about 5%, about 1% toabout 5%, about 1.5% to about 5%, about 1% to about 5%, about 2% toabout 5%, about 2.5% to about 5%, about 3% to about 5%, about 3.5% toabout 5%, or about 4% to about 5%, or about 4.5% to about 5%. In anembodiment, a nucleating agent can be about 0.5%, about 1%, about 1.5%,about 2%, about 2.5%, about 3%, about 4%, or about 5% (w/w). In anembodiment, the polymeric material lacks a nucleating agent. In anembodiment, the polymeric material lacks talc.

In an illustrative embodiment, a chemical blowing agent can be 0 toabout 5% (w/w), about 0.1% to about 5% (w/w), about 0.25% to about 5%,about 0.5% to about 5%, about 0.75% to about 5%, about 1% to about 5%,about 1.5% to about 5%, about 2% to about 5%, about 3% to about 5%,about 4% to about 5%, 0 to about 4% (w/w), about 0.1% to about 4% (w/w),about 0.25% to about 4%, about 0.5% to about 4%, about 0.75% to about4%, about 1% to about 4%, about 1.5% to about 4%, about 2% to about 4%,about 3% to about 4%, 0 to about 3% (w/w), about 0.1% to about 3% (w/w),about 0.25% to about 3%, about 0.5% to about 3%, about 0.75% to about3%, about 1% to about 3%, about 1.5% to about 3%, about 2% to about 3%,0 to about 2%, about 0.1% to about 2% (w/w), about 0.25% to about 2%,about 0.5% to about 2%, about 0.75% to about 2%, about 1% to about 2%,about 1.5% to about 2%, 0 to about 1%, about 0.1% to about 1%, about0.5% to about 1%, or about 0.75% to about 1%. In an illustrativeembodiment, a chemical blowing agent can be about 0.1%, 0.5%, 0.75%, 1%,1.5% or about 2%. In one aspect of the present disclosure, where achemical blowing agent is used, the chemical blowing agent may beintroduced into the material formulation that is added to the hopper.

One example of a physical blowing agent is nitrogen (N₂). The N₂ ispumped into the molten formulation via a port in the extruder as asupercritical fluid. The molten material with the N₂ in suspension thenexits the extruder via a die where a pressure drop occurs. As thepressure drop happens, N₂ moves out of suspension toward the nucleationsites where cells grow. Excess gas blows off after extrusion with theremaining gas trapped in the cells formed in the extrudate. Othersuitable examples of physical blowing agents include, but are notlimited to, carbon dioxide (CO₂), helium, argon, air, pentane, butane,or other alkane mixtures of the foregoing and the like.

In one aspect of the present disclosure, at least one slip agent may beincorporated into the formulation to aid in increasing production rates.Slip agent (also known as a process aid) is a term used to describe ageneral class of materials which are added to the formulation andprovide surface lubrication to the polymer during and after conversion.Slip agents may also reduce or eliminate die drool. Representativeexamples of slip agent materials include amides of fats or fatty acids,such as, but not limited to, erucamide and oleamide. In one exemplaryaspect, amides from oleyl (single unsaturated C-18) through erucyl (C-22single unsaturated) may be used. Other representative examples of slipagent materials include low molecular weight amides andfluoroelastomers. Combinations of two or more slip agents can be used.Slip agents may be provided in a master batch pellet form and blendedwith the resin formulation. One example of a suitable slip agent isAmpacet 102823 Process Aid PE MB LLDPE.

In an embodiment, a slip agent can be about 0% to about 10% (w/w), about0.5% to about 10% (w/w), about 1% to about 10% (w/w), about 2% to about10% (w/w), about 3% to about 10% (w/w), about 4% to about 10% (w/w),about 5% to about 10% (w/w), about 6% to about 10% (w/w), about 7% toabout 10% (w/w), about 8% to about 10% (w/w), about 9% to about 10%(w/w), about 0% to about 9% (w/w), about 0.5% to about 9% (w/w), about1% to about 9% (w/w), about 2% to about 9% (w/w), about 3% to about 9%(w/w), about 4% to about 9% (w/w), about 5% to about 9% (w/w), about 6%to about 9% (w/w), about 7% to about 9% (w/w), about 8% to about 9%(w/w), about 0% to about 8% (w/w), about 0.5% to about 8% (w/w), about1% to about 8% (w/w), about 2% to about 8% (w/w), about 3% to about 8%(w/w), about 4% to about 8% (w/w), about 5% to about 8% (w/w), about 6%to about 8% (w/w), about 7% to about 8% (w/w), about 0% to about 7%(w/w), about 0.5% to about 7% (w/w), about 1% to about 7% (w/w), about2% to about 7% (w/w), about 3% to about 7% (w/w), about 4% to about 7%(w/w), about 5% to about 7% (w/w), about 6% to about 7% (w/w), about 0%to about 6% (w/w), about 0.5% to about 6% (w/w), about 1% to about 6%(w/w), about 2% to about 6% (w/w), about 3% to about 6% (w/w), about 4%to about 6% (w/w), about 5% to about 6% (w/w), about 0% to about 5%(w/w), about 0.5% to about 5% (w/w), about 1% to about 5% (w/w), about2% to about 5% (w/w), about 3% to about 5% (w/w), about 4% to about 5%(w/w), about 0% to about 4% (w/w), about 0.5% to about 4% (w/w), about1% to about 4% (w/w), about 2% to about 4% (w/w), about 3% to about 4%(w/w), about 0% to about 3% (w/w), about 0.5% to about 3% (w/w), about1% to about 3% (w/w), about 2% to about 3% (w/w), about 0% to about 2%(w/w), about 0.5% to about 2% (w/w), about 1% to about 2% (w/w), about0% to about 1% (w/w), or about 0.5% to about 1% (w/w). In an embodiment,a slip agent can be about 0.5%, about 1%, about 2%, about 3%, about 4%,about 5%, about 6%, about 7%, about 8%, about 9%, or about 10% (w/w). Inan embodiment, the formulation lacks a slip agent.

In an embodiment, a colorant can be about 0% to about 20% (w/w), about0% to about 15% (w/w), about 0% to about 10% (w/w), about 0% to about 5%(w/w), about 0% to about 4% (w/w), about 0.1% to about 4%, about 0.25%to about 4%, about 0.5% to about 4%, about 0.75% to about 4%, about 1.0%to about 4%, about 1.5% to about 4%, about 2.0% to about 4%, about 2.5%to about 4%, about 3% to about 4%, about 0% to about 3.0%, about 0% toabout 2.5%, about 0% to about 2.25%, about 0% to about 2.0%, about 0% toabout 1.5%, about 0% to about 1.0%, about 0% to about 0.5%, about 0.1%to about 3.5%, about 0.1% to about 3.0%, about 0.1% to about 2.5%, about0.1% to about 2.0%, about 0.1% to about 1.5%, about 0.1% to about 1.0%,about 1% to about 5%, about 1% to about 10%, about 1% to about 15%,about 1% to about 20%, or about 0.1% to about 0.5%. In an embodiment, aformulation lacks a colorant.

In an embodiment, the formulation comprises:

50-100 wt % of a primary base resin

0-50 wt % of a secondary resin

0-5 wt % of a chemical blowing agent

0.1-20 wt % of a nucleating agent

0-20 wt % of a colorant

0-10 wt % of a slip agent

In another embodiment, the formulation comprises:

50-100 wt % of a primary base resin

0-50 wt % of a secondary resin

0-2 wt % of a chemical blowing agent

0-20 wt % of a physical nucleating agent

0-20 wt % of a colorant

0-10 wt % of a slip agent

In another embodiment, the formulation comprises:

75-85 wt % of a primary base resin

10-20 wt % of a secondary resin

0-0.1 wt % of a chemical blowing agent

0.1-3 wt % of a nucleating agent

0-2 wt % of a colorant

0-4 wt % of a slip agent

In another embodiment, the formulation comprises:

50-99.65 wt % of the primary base resin

0-50 wt % of the secondary resin

0-10 wt % of the slip agent

0-10 wt % of the colorant

0.35-1.5 wt % of nucleating agent

In another embodiment, the formulation comprises:

50-95 wt % of the primary base resin

0-50 wt % of the secondary resin

0-10 wt % of the slip agent

0-10 wt % of the colorant

0.4-1.2 wt % of nucleating agent

In another embodiment, the formulation comprises:

55-85 wt % of the primary base resin

0-50 wt % of the secondary resin

0-10 wt % of the slip agent

0-10 wt % of the colorant

0.45-1.25 wt % of nucleating agent

In another embodiment, the formulation comprises:

50-99.69 wt % of the primary base resin

0-50 wt % of the secondary resin

0-10 wt % of the slip agent

0-10 wt % of the colorant

0.01-1.5 wt % of the primary nucleating agent

0.3-1.7 wt % of the secondary nucleating agent

In another embodiment, the formulation comprises:

50-95 wt % of the primary base resin

0-50 wt % of the secondary resin

0-10 wt % of the slip agent

0-10 wt % of the colorant

0.02-1.0 wt % of the primary nucleating agent

0.4-1.5 wt % of the secondary nucleating agent

In another embodiment, the formulation comprises:

55-85 wt % of the primary base resin

0-50 wt % of the secondary resin

0-10 wt % of the slip agent

0-10 wt % of the colorant

0.03-0.7 wt % of the primary nucleating agent

0.45-1.25 wt % of the secondary nucleating agent

In another embodiment, the formulation comprises:

78-83 wt % of a primary base resin

14-16 wt % of a secondary resin

0-0.05 wt % of a chemical blowing agent

0.25-2 wt % of a nucleating agent

1-2 wt % of a colorant

1.5-3.5 wt % of a slip agent

In the preceding embodiments, the primary base resin may comprise apolypropylene. Suitably, the primary base resin comprises at least oneof Borealis WB140 HMS polypropylene homopolymer and Braskem F020HCpolypropylene homopolymer. More suitably, the primary base resin isBorealis WB140 HMS polypropylene homopolymer.

In the preceding embodiments, the secondary resin may comprise at leastone polypropylene copolymer or polypropylene homopolymer. Suitably, thesecondary resin comprises at least one of Braskem F020HC polypropylenehomopolymer and PP 527K (available from Sabic). More suitably, thesecondary resin is Braskem F020HC polypropylene homopolymer.

In the preceding embodiments, the chemical blowing agent may comprisecitric acid, or a citric acid-based material. Suitably the chemicalblowing agent is Hydrocerol™ CF-40E (available from ClariantCorporation).

In the preceding embodiments, the nucleating agent may comprise talc,CaCO₃, mica and mixtures thereof. Suitably, the nucleating agent is oneor more of HT4HP talc (available from Heritage Plastics) and HT6000Linear Low Density Polyethylene (LLDPE) (available from HeritagePlastics) and Techmer PM PPM 16466 Silica. More suitably, the nucleatingagent is HT4HP talc (available from Heritage Plastics) or Techmer PM PPM16466 Silica. A primary nucleating agent may be defined as a chemicalblowing agent or chemical foaming agent, itself comprising a nucleatingagent. In a particular embodiment, a primary nucleating agent isHydrocerol™ CF-40E™ (available from Clariant Corporation). In aparticular embodiment, a secondary nucleating agent is selected fromHPR-803i fibers (available from Milliken) or talc

In the preceding embodiments, the colorant may comprise at least one ofColortech 11933-19 TiO₂ PP and Cell Stabilizer. Suitably, the colorantis Colortech 11933-19 TiO₂ PP.

In the preceding embodiments, the slip agent may comprise one or moreamides of fats or fatty acids, such as erucamide and oleamide. The slipagent may also comprise one or more low molecular weight amides andfluoroelastomers. Suitably, the slip agent is Ampacet 102823 Process AidPE MB LLDPE.

The method of any of the preceding embodiments may also comprise addingCO₂ to the formulation prior to extrusion at a rate of 1-4 lbs/hr. Inone example, the CO₂ is added at a rate of 2-3 lbs/hr. In anotherexample, the CO₂ is added at a rate of 2.2-2.8 lbs/hr. Such practice mayalso be referred to as adding a physical blowing agent.

In illustrative embodiments, the middle cellular non-aromatic polymericlayer 12M has a density in a range of about 0.01 g/cm³ to about 0.19g/cm³. In illustrative embodiments, the middle cellular non-aromaticpolymeric layer has a density in a range of about 0.05 g/cm³ to about0.19 g/cm³. In illustrative embodiments, the middle cellularnon-aromatic polymeric layer has a density in a range of about 0.1 g/cm³to about 0.185 g/cm³.

Outer polymeric layer 12O and inner polymeric layer 12I are, forexample, made a non-aromatic polymer. Inner polymeric layer 12I isspaced apart from outer polymeric layer 12O so as to locate middleinsulative cellular non-aromatic polymeric layer 12M therebetween. Innerpolymer layer 12I is located between interior region 14 and middleinsulative cellular non-aromatic polymeric layer 12M as shown, forexample, in FIG. 2.

In one illustrative example, outer and inner polymeric layers 12O, 12Iare made from polypropylene. While inner and outer polymeric layers 12O,12I may be made from the same material, they may also be made fromdifferent materials so as to achieve desired performance characteristicsof the container.

Container 10 includes, from top to bottom, a brim 16 and a body 18 asshown in FIG. 1. Brim 16 is appended to a top portion of body 18 andarranged to define a mouth 20 opening into interior region 14 formed inbody 18. In one example, container 10 is an insulative drink cup andbrim 16 is adapted to mate with a lid which covers and closes mouth 20.

Container 10 is formed using container-manufacturing process 100 asshown, for example in FIGS. 3A-4. Container-manufacturing process 100is, for example, a multi-layer co-extruded blow molding operation assuggested in FIGS. 3A and 4. Container-manufacturing process 100includes an inner layer extrusion operation 102, a middle layerextrusion operation 104, an outer layer extrusion operation 106, and atube forming operation 108 as shown in FIGS. 3A and 4. Inner layerextrusion operation 102 occurs when a first extruder 131 extrudes aninner layer 142 which provides inner polymeric layer 12I. Middle layerextrusion operation 104 occurs when a second extruder 132 extrudes amiddle layer 142 which provides middle cellular non-aromatic polymericlayer 12M. Outer layer extrusion operation 106 occurs when a thirdextruder 133 extrudes an outer layer 143 which provides outer polymericlayer 12O. All three layers 141, 142, 143 are brought together in orderduring tube forming operation 108 in a die 140 to establish multi-layertube 12 as shown in FIG. 3A.

While container-manufacturing process 100 shows the extrusion of threelayers, any number of inner layers, middle layers, and outer layers maybe extruded by any number of extrudes. These various layers may then becombined in the die to establish a multi-layer tube.

Container-manufacturing process 100 further includes an extrudingmulti-layer tube operation 110, a mold closing operation 112, an airpumping operation 114, a mold opening operation 116, and a vesselremoving operation 118 as shown, for example, in FIGS. 3B-4. Duringextruding multi-layer tube operation 110, extruders 131, 132, 133continue to extrude associated layers 141, 142, 143 so that multi-layertube 12 is extruded between two mold halves 134A, 134B included in amold 134 as shown in FIG. 3A. During mold closing operation 112, moldhalves 134A, 134B are brought together to establish a mold cavity 134Cformed in mold 134. Next, air is pumped into a portion of multi-layertube 12 trapped in mold cavity 134C to cause multi-layer tube 12 toexpand and take on a shape of mold cavity 134C and establish a vessel 22including an interior space 24 filled with air. However, in anotherexample vacuum may be applied to the multi-layer tube 12 in mold cavity134 to take on the shape of mold cavity 134. During mold openingoperation 116, mold halves 134A, 134B open and move away from one antheras shown in FIG. 3C. Vessel 22 is removed from mold 134.

In one example, a continuous extrusion process may be used incombination with a rotary blow molding machine. In this example, acontinuous multi-layer tube is extruded and a series of molds includedin the rotary blow molding machine rotate relative to the multi-layertube. As molds approach the extruders forming the multi-layer tube, theybegin to move from an opened arrangement to a closed arrangementtrapping a portion of the multi-layer tube in a mold cavity formed inthe mold. As the molds move away from the extruders forming themulti-layer tube, they move from the closed position to an openedposition where a vessel is ejected from the mold cavity. One example ofa rotary extrusion blow molding machine is available from WilmingtonMachinery of Wilmington, N.C.

In another example, a continuous extrusion process may be used incombination with a shuttle blow molding machine. In this example, afirst mold on a track moves to an opened position, slides over toreceive the multi-layer tube in the mold cavity, and moves to a closedposition. The first mold then slides away from the multi-layer tubewhere air is pumped into the interior space to cause the multi-layertube to assume the mold shape. When the first mold moves away from themulti-layer tube, a second mold moves to an opened position, slides overto receive the continuously extruded multi-layer tube in a mold cavityof the second mold, and moves to a closed position. The second mold thenslides away from the multi-layer tube where air is pumped into theinterior space. While the second mold moves away from the multi-layertube, the first mold moves to the opened position ejecting the vessel tostart the process over again. One example of a shuttle blow moldingmachine is available from Graham Engineering Corporation of York, Pa.

Container-manufacturing process 100 may include an optional step ofinserting a label or other item in the mold cavity prior to receivingthe multi-layer tube 12 therein. As a result, body 18 may be formed witha printed label or other feature coupled to the side wall 28 duringmolding. Thus, container-manufacturing process 100 is capable of an-moldlabeling operation.

Container-manufacturing process 100 further includes a cutting operation120 and a forming operation 122 as shown in FIG. 4. During cuttingoperation 120, a top portion 26 of vessel 22 is cut and separated fromvessel 22 to cause body 18 to be established. As shown in FIGS. 5 and 6,body 18 includes a side wall 28 and a floor 30. Floor 30 is appended toa lower portion of side wall 28 and cooperates with side wall 28 todefine interior region 14 as shown in FIG. 5. Body 18 may then beaccumulated and transported to forming operation 122 where abrim-forming step and a printing step may be performed. During thebrim-forming step, brim 16 is formed on body 18 using a brim-formingmachine (not shown) where a top portion of body 18 is rolled downwardlytoward side wall 28. During the printing step, graphics, words, or otherindicia may be printed on outwardly facing surface of outer polymericlayer 12O. Once brim 16 is established on body 18, container 10 isestablished.

Body 18 is shown, for example, in FIGS. 5 and 6 after cutting operation120 has been performed on vessel 22. Body 18 includes side wall 28 andfloor 30 as shown in FIGS. 5 and 6. An aperture 32 is formed as a resultof cutting operation 120. Aperture 32 will become mouth 20 after thebrim-forming step has occurred.

Body 218 is formed using container-manufacturing process 300 as shown,for example in FIGS. 7A-8. Container-manufacturing process 300 is, forexample, a multi-layer co-extruded blow molding operation as suggestedin FIGS. 7A-8. Container-manufacturing operation 300 includes innerlayer extrusion operation 102, middle layer extrusion operation 104,outer layer extrusion operation 106, and tube forming operation 108 asshown in FIGS. 3A, 4, 7A, and 8. Inner layer extrusion operation 102occurs when first extruder 131 extrudes an inner layer 141 whichprovides inner polymeric layer 12I. Middle layer extrusion operation 104occurs when second extruder 132 extrudes a middle layer 142 whichprovides middle insulative cellular non-aromatic polymeric layer 12M.Outer layer extrusion operation 106 occurs when third extruder 133extrudes an outer layer 143 which provides outer polymeric layer 12O.All three layers 141, 142, 143 are brought together in die 140 duringtube forming operation 108 to establish multi-layer tube 12 as shown inFIG. 7A.

Container-manufacturing process 300 further includes extrudingmulti-layer tube operation 110, mold closing operation 112, air pumpingoperation 114, mold opening operation 116, and vessel removing operation118 as shown, for example, in FIGS. 7B-8. During extruding multi-layertube operation 110, extruders 131, 132, 133 continue to extrudeassociated layers 141, 142, 143 so that multi-layer tube 12 is extrudedbetween two mold halves 134A, 134B included in mold 134 as shown in FIG.7A. During mold closing operation 112, mold halves 134A, 134B arebrought together to establish mold cavity 134C formed in mold 134. Next,air is pumped into a portion of multi-layer tube 12 trapped in moldcavity 134C to cause multi-layer tube 12 to expand and take on the shapeof mold cavity 134C and establish vessel 22 including interior space 24filled with air. During mold opening operation 116, mold halves 134A,134B open and move away from one anther as shown in FIG. 7C. Vessel 22is removed from mold 134.

Container-manufacturing process 300 further includes a cutting operation320, a floor forming operation 322, a floor coupling operation 324, anda body establishing operation 326 as shown in FIG. 8. During cuttingoperation 320, a top portion 226 of vessel 22 and a bottom portion 227of vessel 22 is cut and separated from vessel 22 to cause a side wall228 to be established as suggested in FIGS. 7C and 7D. During floorforming operation 322, a floor 230 is formed. Floor 230 may be injectionmolded, thermoformed, or any other suitable alternative. During floorcoupling operation 324, floor 230 is coupled to a bottom portion of sidewall 228. Body 218 is established during body establishing operation 326as shown in FIGS. 7D, 9, and 10.

Body 218 includes side wall 228 and floor 230 as shown in FIGS. 9 and10. Floor 230 is coupled to the lower portion of side wall 228 andcooperates with side wall 228 to define interior region 214 as shown inFIG. 9. In one example, floor 230 is coupled by adhesive to floor 230.In another example, floor 230 is coupled by a heat seal to floor 230.However, any suitable means for coupling floor 230 to side wall 228 maybe used.

Body 218 may then be accumulated and transported to forming operation328 where a brim-forming step and a printing step may be performed.During the brim-forming step, a brim is formed on body 218 using abrim-forming machine (not shown) where a top portion of body 218 isrolled downwardly toward side wall 228. During the printing step,graphics, words, or other indicia may be printed on outwardly facingsurface of outer polymeric layer 12O. Once the brim is established onbody 218, a container is established.

Another embodiment of a container 410 in accordance with the presentdisclosure is shown, for example, in FIGS. 11 and 12. Container 410 ismade using one of the container-manufacturing processes 100, 300.Container 410 includes a brim 416, a side wall 428, a floor 430 asshown, for example in FIGS. 11 and 12. Container 410 has relativelyvertical side wall 428 as compared to container 10 which has an angledside wall 28. In addition, side wall 428 is formed to include aplurality of ribs 434 as shown in FIGS. 11 and 12. Ribs 434 may be usedto maximize stack strength of container 410.

Another embodiment of a container 510 in accordance with the presentdisclosure is shown, for example, in FIGS. 13A and 13E. Container 510 ismade from another embodiment of a multi-layer tube that includes aninner polymeric layer 512I, middle insulative cellular non-aromaticpolymeric layer 512M, and outer polymeric layer 512O as shown in FIGS.13C and 13D. Container 510 has, for example, an interior region 514configured to hold about 750 ml. Container 510 weights about 44 grams.

Inner polymeric layer 512I is made from a polymeric material includinghigh density polyethylene and colorant. Outer polymeric layer 512O ismade from a polymeric material including high density polyethylene.Middle insulative cellular non-aromatic polymeric layer 512M is madefrom an insulative cellular non-aromatic polymeric material thatincludes high density polyethylene and a talc nucleating agent assuggested in FIG. 13D.

Container 510 includes, from top to bottom, a brim 516 and a body 518 asshown in FIG. 13A. Brim 516 is appended to a top portion of body 518 andarranged to define a mouth 520 opening into interior region 514 formedin body 518. In one example, container 510 is an insulative drink cupand brim 516 is adapted to mate with a lid which covers and closes mouth520. Body 518 includes a side wall 528 and a floor 530 as shown in FIG.13B.

In one example, containers 510 were formed from a multi-layer tube. Themiddle layer used to form middle insulative cellular non-aromaticpolymeric material 512M had a density of about 0.83 grams per cubiccentimeter. After mating the inner layer with the inner and outer layersand forming container 510, container 510 had a density of about 0.95grams per cubic centimeter.

In another example, operation of the second extruder 132 was optimizedto minimize density of the middle layer. In addition, thicknesses ofinner and outer layers were minimized. As a result, inner polymericlayer 512I is about 15% of a total thickness of side wall 528 ofcontainer 510. Outer polymeric layer 512O is about 15% of the totalthickness of side wall 528 of container 510. Middle insulative cellularnon-aromatic polymeric material 512M is about 70% the total thickness ofside wall 528 of container 510. Container 510, as a result, has adensity of about 0.87 grams per cubic centimeter after optimization.

Inner polymeric layer 512I of container 510 has a weight of about 32grams. Outer polymeric layer 512O of container 510 has a weight of about40 grams. Middle insulative cellular non-aromatic polymeric material512M has a weight of about 35 grams.

The optimized container 510 was tested in an Instron tester to determinetop load performance as suggested in FIG. 13E. Table 1 shows theperformance of several containers 510 (including middle cellular layer512M) tested vs. several high density polyethylene containers (excludingmiddle cellular layer 512M).

TABLE 1 Comparison of Non-Cellular Containers vs. Cellular Containers intop-loading performance (higher collapse force is better and lower massof container is better) Container Type Mass of Container (grams)Collapse Force (lbs) Non-Cellular 44.0 57 Non-Cellular 40.0 36Non-Cellular 35.0 26 Cellular 40.0 58 Cellular 35.0 41 Cellular 32.0 32

The results of the top-loading testing show that containers 510withstood higher collapse force even when about 10% lighter thannon-cellular containers. As a result, container 510 provides for a moresustainable container as less material is a stronger container isprovided that maximizes stack strength.

Another embodiment of a container 610 in accordance with the presentdisclosure is shown, for example, in FIGS. 14B, 14D, and 14E. Container610 is made from another embodiment of a multi-layer tube 612 thatincludes an inner polymeric layer 612I, middle insulative cellularnon-aromatic polymeric layer 612M, and outer polymeric layer 612O asshown in FIG. 14C. Container 610 has, for example, an interior region614.

Container 610 includes, from top to bottom, a neck 616 and a body 618 asshown in FIG. 14B. Neck 616 is appended to a top portion of body 618 andarranged to define a mouth 620 opening into interior region 614 formedin body 618. In one example, container 610 is a shampoo bottle and neck616 is adapted to mate with a lid which covers and closes mouth 620.Body 618 includes a side wall 628 and a floor 630 as shown in FIG. 14B.

In one example, containers 610 were formed from a multi-layer tube. Themiddle layer used to form middle insulative cellular non-aromaticpolymeric layer 612M had a density of about 0.62 grams per cubiccentimeter. After mating the inner layer with the inner and outer layersand forming container 610, container 610 has a density of about 0.88grams per cubic centimeter as suggested in FIG. 14D. Another embodimentof a container 610A has a density of about 0.81 grams per cubiccentimeter as suggested in FIG. 14E.

Container 710 in accordance with the present disclosure is shown in FIG.15. Container 710 is made from a multi-layer tube including an innerpolymeric layer, an outer polymeric layer, and a middle cellularnon-aromatic polymeric layer. As shown in FIG. 15, container 710includes a floor 730, a side wall 728 appended to floor 730 to extendupwardly generally perpendicular to floor 730, and a neck 716 appendedto an upper end of side wall 728. Neck 716 defines a mouth 720 arrangedto open into an interior region 714 formed between floor 730 and sidewall 728.

Container 710 was also subjected to top-load testing as suggested inFIGS. 18 and 20. To begin the top-load testing, an Instron tester isturned on along with a computer coupled to the Instron tester to obtaindata and control the tester. Test parameters are then loaded into thecomputer. The test parameters include a deflection of about 0.200inches, a speed of about 2 inches per minute, and a minimum load of 45pounds. After the test parameters are input, a sample container isplaced on a platform included in the Instron tester. A test unitincluded in the Instron tester is then moved to just barely engage thesample container. The test routine is then initiated. As the test unitmoves down deforming the sample container, force vs. displacement ismeasured. Higher forces measured indicate a better performing container.

As shown in FIG. 18 various containers with the same shape butsubstantially the same mass of about 56 grams were subjected to top-loadtesting. A control container 800 includes only a solid monolayer ofpolymeric material having a density of about 0.955 g/cm³. A first samplecontainer 801 includes only a foam monolayer of polymeric materialhaving a density of about 0.51 g/cm³. A second sample container 802includes only a foam monolayer of polymeric material having a density ofabout 0.61 g/cm³. A third sample container 803 includes only a foammonolayer of polymeric material having a density of about 0.71 g/cm³. Afourth sample container 804 was made from a multi-layer tube includingan inner polymeric layer, an outer polymeric layer, and a middlecellular non-aromatic polymeric layer located therebetween. Fourthsample container 804 had a density of about 0.51 g/cm³. A fifth samplecontainer 805 was made from a multi-layer tube including an innerpolymeric layer, an outer polymeric layer, and a middle cellularnon-aromatic polymeric layer located therebetween. Fifth samplecontainer 805 had a density of about 0.61 g/cm³. A sixth samplecontainer 806 was made from a multi-layer tube including an innerpolymeric layer, an outer polymeric layer, and a middle cellularnon-aromatic polymeric layer located therebetween. Sixth samplecontainer 806 had a density of about 0.71 g/cm³. A seventh samplecontainer 807 was made from a multi-layer tube including an innerpolymeric layer, an outer polymeric layer, and a middle cellularnon-aromatic polymeric layer located therebetween. Seventh samplecontainer 807 had a density of about 0.91 g/cm³.

As shown in FIG. 18, fifth, sixth, and seventh sample containers 805,806, and 807 all peaked at higher force than control container 800. Inaddition, sixth sample container 806 had the highest peak force whencompared with higher and lower density sample containers 807, 805, 804.The graph shown in FIG. 18 indicates that containers made from themulti-layer tube and having a density less than the density of thecontrol container 800 and higher than about 0.51 g/cm³ have between 5%to about 30% increased compressive strength. In one example, sixthsample 806 container peaked at about 215 pounds while control container800 peaked at about 170 pounds providing an increase of about 26% intop-load performance. In another example, seventh sample container 807peaked at about 195 pounds providing an increase of about 15% intop-load performance. In still yet another example, fifth samplecontainer 805 peaked at about 185 pounds providing an increase of about9% in top-load performance.

As shown in FIG. 20 various containers with the same shape butsubstantially the same wall thickness of about 0.039 inches were subjectto top-load testing. A control container 900 includes only a solidmonolayer of polymeric material having a density of about 0.955 g/cm³. Afirst sample container 901 includes only a foam monolayer of polymericmaterial having a density of about 0.51 g/cm³. A second sample container902 includes only a foam monolayer of polymeric material having adensity of about 0.61 g/cm³. A third sample container 903 includes onlya foam monolayer of polymeric material having a density of about 0.71g/cm³. A fourth sample container 904 was made from a multi-layer tubeincluding an inner polymeric layer, an outer polymeric layer, and amiddle cellular non-aromatic polymeric layer located therebetween.Fourth sample container 904 had a density of about 0.51 g/cm³. A fifthsample container 905 was made from a multi-layer tube including an innerpolymeric layer, an outer polymeric layer, and a middle cellularnon-aromatic polymeric layer located therebetween. Fifth samplecontainer 905 had a density of about 0.61 g/cm³. A sixth samplecontainer 906 was made from a multi-layer tube including an innerpolymeric layer, an outer polymeric layer, and a middle cellularnon-aromatic polymeric layer located therebetween. Sixth samplecontainer 906 had a density of about 0.71 g/cm³. A seventh samplecontainer 907 was made from a multi-layer tube including an innerpolymeric layer, an outer polymeric layer, and a middle cellularnon-aromatic polymeric layer located therebetween. Seventh samplecontainer 907 had a density of about 0.91 g/cm³.

As shown in FIG. 20, fourth fifth, sixth, and seventh sample containers904, 905, 906, and 907 all had performance between control container 900and first, second, and third sample containers 901, 902, 903. When wallthickness is maintained and density is varied, higher density containerswill be heavier, and thus, provide more material to resist deformation.As a result, the graph of FIG. 20 shows that those container includinginner and outer polymeric layers provide substantially increasedstrength when compared with containers having only the foamed monolayer.

Container 710 was also subjected to side-wall rigidity testing assuggested in FIGS. 19 and 21. To begin the side-wall rigidity testing, aside-wall rigidity tester 750 is turned on as shown in FIGS. 16 and 17.The side-wall rigidity tester 750 includes a Y-bar 752, a T-bar 754, atravel gauge 756, and a force gauge 758 as shown in FIGS. 16 and 17.Y-bar 752 is used to retain a sample container in place during theside-wall rigidity testing. T-bar 754 is coupled to the force gauge 758and used to deform a side wall of the sample container as force gauge758 moves toward the sample container. The travel gauge 758 is coupledto the force gauge 758 to move therewith and is configured to measure adistance of displacement that the T-bar 754 deforms the side wall of thecontainer. The force gauge 758 measure force exerted on T-bar 754 by thesample container as the sample container resists movement of the forcegauge 758 and T-bar 754 moving toward the sample container.

The sidewall-rigidity testing begins by placing a sample containerbetween T-bar 754 and Y-bar 752. T-bar 754 and gauges 756, 768 are thenmoved until T-bar 754 contacts the side wall of the sample container.The force gauge 758 and the travel gauge 756 are both zeroed out. Speedof movement of the force gauge 758 and T-bar 754 is set to 100. T-bar754 and force gauge 758 then engage and deform the side wall of thesample container until the force gauge 758 has moved about 0.25 inchesas measured by the travel gauge 756. Force is measured in pounds throughmovement of the force gauge 758 and the T-bar 754. Higher forcesmeasured indicate a better performing container.

As shown in FIG. 19 various containers with the same shape butsubstantially the same mass of about 56 grams were subjected toside-wall rigidity testing. Control container 800, monolayer foamcontainers 801, 802, 803, and multi-layer containers 804, 805, 806, 807were subjected to side-wall rigidity testing. As shown in FIG. 19,fifth, sixth, and seventh sample containers 805, 806, and 807 all peakedat higher force than control container 800. In addition, sixth samplecontainer 806 had the highest peak force when compared with higher andlower density sample containers 807, 805, 804.

The graph shown in FIG. 19 indicates that containers made from themulti-layer tube and having a density less than the density of thecontrol container 800 and higher than about 0.51 g/cm³ have between 3%to about 30% increased shear strength. In one example, sixth sample 806container peaked at about 4.7 pounds while control container 800 peakedat about 4.1 pounds providing an increase of about 24% in side-wallrigidity performance. In another example, seventh sample container 807peaked at about 4.7 pounds providing an increase of about 15% inside-load rigidity performance. In still yet another example, fifthsample container 805 peaked at about 4.2 pounds providing an increase ofabout 4% in side-wall rigidity performance.

As shown in FIG. 21 various containers with the same shape butsubstantially the same wall thickness of about 0.039 inches were subjectto side-wall rigidity testing. Control container 900, monolayer foamcontainers 901, 902, 903, and multi-layer containers 904, 905, 906, 907were subjected to side-wall rigidity testing. As shown in FIG. 21,fourth fifth, sixth, and seventh sample containers 904, 905, 906, and907 all had performance between control container 900 and first, second,and third sample containers 901, 902, 903. When wall thickness ismaintained and density is varied, higher density containers will beheavier, and thus, provide more material to resist deformation. As aresult, the graph of FIG. 21 shows that those container including innerand outer polymeric layers provide substantially increased strength whencompared with containers having only the foamed monolayer.

A vessel in accordance with present disclosure includes a floor and asidewall coupled to the floor and arranged to extend upwardly fromground underlying the floor and to cooperate with the floor to define aninterior product-storage region therebetween. The floor and the sidewall cooperate to form a monolithic element comprising an innerpolymeric layer forming a boundary of the interior product-storageregion, an outer polymeric layer arranged to lie in spaced-apartrelation to the inner polymeric layer to define a core chambertherebetween, and a middle cellular non-aromatic polymeric materiallocated in the core chamber to lie between the outer polymeric layer andthe inner polymeric layer. The inner polymeric layer, the outerpolymeric layer, and a middle cellular non-aromatic polymeric materialcooperate to provide means for maximizing a compressive strength of thevessel as tested by top-load testing and a shear strength of the vesselas tested by side-wall rigidity testing while minimizing a weight of thevessel.

The compressive strength and the shear strength of the vessel may berelated to the physical dimensions of the container. The physicaldimensions of the container allow for the calculation of a moment areaof Inertia for the container as suggested in FIG. 22. The moment of areaof inertia of an object about a given axis describes how difficult it isto change an angular momentum of the object about that axis. The momentarea of inertia also describes an amount of mass included in in anobject and how far each bit of mass is from the axis. The farther theobject's mass is from the axis, the more rotational inertia the objecthas. As a result, more force is required to change the objects rotationrate.

Thus, the compressive strength and the shear strength of the vessel areproportional to the moment area of inertia. The moment area of inertiarelative to each axis is defined by the equations below:

$I_{x} = {\frac{\pi}{4}\left( {r_{o}^{4} - r_{i}^{4}} \right)}$$I_{y} = {\frac{\pi}{4}\left( {r_{o}^{4} - r_{i}^{4}} \right)}$$I_{z} = {\frac{\pi}{2}\left( {r_{o}^{4} - r_{i}^{4}} \right)}$The relationship between the moment area of inertia and the vessel andthe compressive and shear strengths may be referred to as the I-beameffect.

In an illustrative example, a vessel 1010 was sectioned along the X-Yplane as shown in FIG. 22. Vessel 1010 was formed from a multi-layertube including an inner polymeric layer 1012I, an outer polymeric layer1012O, and a middle cellular non-aromatic polymeric layer 1012M as shownin FIG. 22. An outer surface 1014 of outer polymeric layer 1012Oprovides the value r_(o) used in the equations above. An inner surface1016 provided by inner polymeric layer 1012I provides the value r_(i)used in the equations above.

The following numbered clauses include embodiments that are contemplatedand non-limiting:

Clause 1. A vessel comprising

a floor and

a side wall coupled to the floor and arranged to extend upwardly fromground underlying the floor and to cooperate with the floor to define aninterior product-storage region therebetween,

wherein the floor and the side wall cooperate to form a monolithicelement comprising an inner polymeric layer forming a boundary of theinterior product-storage region, an outer polymeric layer arranged tolie in spaced-apart relation to the inner polymeric layer to define acore chamber therebetween, and a middle cellular non-aromatic polymericmaterial located in the core chamber to lie between the outer polymericlayer and the inner polymeric layer, and

wherein the middle cellular non-aromatic polymeric material has adensity in a range of about 0.01 g/cm³ to about 0.19 g/cm³.

Clause 2. A vessel comprising

a floor and

a side wall coupled to the floor and arranged to extend upwardly fromground underlying the floor and to cooperate with the floor to define aninterior product-storage region therebetween,

wherein the floor and the side wall cooperate to form a monolithicelement comprising an inner polymeric layer forming a boundary of theinterior product-storage region, an outer polymeric layer arranged tolie in spaced-apart relation to the inner polymeric layer to define acore chamber therebetween, and a middle cellular non-aromatic polymericmaterial located in the core chamber to lie between the outer polymericlayer and the inner polymeric layer, and

wherein the inner polymeric layer, the outer polymeric layer, and amiddle cellular non-aromatic polymeric material cooperate to providemeans for maximizing a compressive strength of the vessel as tested bytop-load testing and a shear strength of the vessel as tested byside-wall rigidity testing while minimizing a weight of the vessel.

Clause 3. A vessel comprising

a floor and

a side wall coupled to the floor and arranged to extend upwardly fromground underlying the floor and to cooperate with the floor to define aninterior product-storage region therebetween,

wherein the floor and the side wall cooperate to form a monolithicelement comprising an inner polymeric layer forming a boundary of theinterior product-storage region, an outer polymeric layer arranged tolie in spaced-apart relation to the inner polymeric layer to define acore chamber therebetween, and a middle cellular polymeric materiallocated in the core chamber to lie between the outer polymeric layer andthe inner polymeric layer, and

wherein the inner polymeric layer, the outer polymeric layer, and amiddle cellular non-aromatic polymeric material cooperate to maximizeresistance to a collapse force while minimizing a weight of the vessel.

Clause 4. The vessel of any preceding clause, wherein the middlecellular non-aromatic polymeric material comprises polypropylene.

Clause 5. The vessel of any preceding clause, wherein the density of themiddle cellular non-aromatic polymeric material is in a range of about0.1 g/cm³ to about 0.185 g/cm³.

Clause 6. The vessel of any preceding clause, wherein each of the innerpolymeric layer, the outer polymeric layer comprise polypropylene.

Clause 7. The vessel of any preceding clause, wherein each of the innerpolymeric layer, the outer polymeric layer comprise polypropylene.

Clause 8. The vessel of any preceding clause, wherein the middlecellular non-aromatic polymeric material comprises high-densitypolyethylene.

Clause 9. The vessel of any preceding clause, wherein the density of themiddle cellular non-aromatic polymeric material is in a range of about0.1 g/cm³ to about 0.185 g/cm³.

Clause 10. The vessel of any preceding clause, wherein each of the innerpolymeric layer, the outer polymeric layer comprise polypropylene.

Clause 11. The vessel of any preceding clause, wherein the density ofthe middle cellular non-aromatic polymeric material is in a range ofabout 0.1 g/cm³ to about 0.185 g/cm³.

Clause 12. The vessel of any preceding clause, wherein each of the innerpolymeric layer, the outer polymeric layer, and the middle cellularnon-aromatic polymeric material comprises polypropylene.

Clause 13. The vessel of any preceding clause, further comprising a brimcoupled to an upper portion of the side wall and formed to include amouth opening into the interior product-storage region.

Clause 14. The vessel of any preceding clause, wherein the brim iscoupled to each of the inner polymeric layer and the outer polymericlayer to close an annular opening into a portion of the core chamberformed in the side wall.

Clause 15. The vessel of any preceding clause, wherein the middlecellular non-aromatic polymeric material is the only material located inthe core chamber.

Clause 16. The vessel of any preceding clause, wherein the middlecellular non-aromatic polymeric material is arranged to fill the corechamber completely.

Clause 17. The vessel of any preceding clause, wherein the middlecellular non-aromatic polymeric material comprises polypropylene.

Clause 18. The vessel of any preceding clause, wherein the density ofthe middle cellular non-aromatic polymeric material is in a range ofabout 0.1 g/cm³ to about 0.185 g/cm³.

Clause 19. The vessel of any preceding clause, wherein each of the innerpolymeric layer, the outer polymeric layer comprise polypropylene.

Clause 20. The vessel of any preceding clause, wherein the middlecellular non-aromatic polymeric material comprises polypropylene.

Clause 21. The vessel of any preceding clause, wherein the density ofthe middle cellular non-aromatic polymeric material is in a range ofabout 0.1 g/cm³ to about 0.185 g/cm³.

Clause 22. The vessel of any preceding clause, wherein the vessel has anaverage density in a density range of about 0.51 g/cm³ to about 0.91g/cm³.

Clause 23. The vessel of any preceding clause, wherein the compressionstrength of the vessel is greater than a compression strength of acontrol vessel having a mass about the same as a mass of the vessel anda shape about the same as a shape of the vessel.

Clause 24. The vessel of any preceding clause, wherein the compressionstrength of the vessel is about 5% to about 30% greater than thecompression strength of the control vessel.

Clause 25. The vessel of any preceding clause, wherein the shearstrength of the vessel is greater than a shear strength of a controlvessel having a mass about the same as a mass of the vessel and a shapeabout the same as a shape of the vessel.

Clause 26. The vessel of any preceding clause, wherein the compressionstrength of the vessel is about 3% to about 30% greater the compressionstrength of the control vessel.

Clause 27. The vessel of any preceding clause, wherein the averagedensity is about 0.91 g/cm³.

Clause 28. The vessel of any preceding clause, wherein the compressionstrength of the vessel is about 9% greater than a compression strengthof a control vessel having a mass about the same as a mass of the vessela shape about the same as a shape of the vessel.

Clause 29. The vessel of any preceding clause, wherein the shearstrength of the vessel is about 4% greater than a shear strength of acontrol vessel having a mass about the same as a mass of the vessel anda shape about the same as a shape of the vessel.

Clause 30. The vessel of any preceding clause, wherein the density rangeis about 0.6 g/cm³ to about 0.8 g/cm³.

Clause 31. The vessel of any preceding clause, wherein the averagedensity is about 0.61 g/cm³.

Clause 32. The vessel of any preceding clause, wherein the compressionstrength of the vessel is about 15% greater than a compression strengthof a control vessel having a mass about the same as a mass of the vessela shape about the same as a shape of the vessel.

Clause 33. The vessel of any preceding clause, wherein the shearstrength of the vessel is about 15% greater than a shear strength of acontrol vessel having a mass about the same as a mass of the vessel anda shape about the same as a shape of the vessel.

Clause 34. The vessel of any preceding clause, wherein the averagedensity is about 0.71 g/cm³.

Clause 35. The vessel of any preceding clause, wherein the compressionstrength of the vessel is about 26% greater than a compression strengthof a control vessel having a mass about the same as a mass of the vesseland a shape about the same as a shape of the vessel.

Clause 36. The vessel of any preceding clause, wherein the shearstrength of the vessel is about 24% greater than a shear strength of acontrol vessel having a mass about the same as a mass of the vessel anda shape about the same as a shape of the vessel.

Clause 37. The vessel of any preceding clause, wherein the shearstrength of the vessel is about 24% greater than a shear strength of acontrol vessel having a mass about the same as a mass of the vessel anda shape about the same as a shape of the vessel.

Clause 38. The vessel of any preceding clause, wherein the vessel has amass of about 56 grams.

Clause 39. The vessel of any preceding clause, wherein the density ofthe middle cellular polymeric material is in a range of about 0.1 g/cm³to about 0.185 g/cm³.

Clause 40. The vessel of any preceding clause, wherein the collapseforce required to collapse the vessel is greater than a collapse forcerequired to collapse a non-cellular vessel having a shape about the sameas a shape of the vessel.

Clause 41. The vessel of any preceding clause, wherein a mass of thevessel is about equal to a mass of the non-cellular vessel.

Clause 42. The vessel of any preceding clause, wherein the collapseforce required to collapse the vessel is about 55% to about 65% greaterthan the collapse force required to collapse the non-cellular vessel.

Clause 43. The vessel of any preceding clause, wherein the collapseforce required to collapse the vessel is about 58% greater than thecollapse force required to collapse the non-cellular vessel.

Clause 44. The vessel of any preceding clause, wherein the mass is about35 grams.

Clause 45. The vessel of any preceding clause, wherein the collapseforce required to collapse the vessel is about 61% greater than thecollapse force required to collapse the non-cellular vessel.

Clause 46. The vessel of any preceding clause, wherein the mass is about40 grams.

Clause 47. The vessel of any preceding clause, wherein a mass of thevessel is less than a mass of the non-cellular vessel.

Clause 48. The vessel of any preceding clause, wherein the collapseforce required to collapse the vessel is about 1% to about 25% greaterthan a collapse force required to collapse the non-cellular vessel.

Clause 49. The vessel of any preceding clause, wherein a mass of thevessel is about 32 grams and a mass of the non-cellular vessel is about35 grams.

Clause 50. The vessel of any preceding clause, wherein the collapseforce required to collapse the vessel is about 23% greater than thecollapse force required to collapse the non-cellular vessel.

Clause 51. The vessel of any preceding clause, wherein a mass of thevessel is about 35 grams and a mass of the non-cellular vessel is about40 grams.

Clause 52. The vessel of any preceding clause, wherein the collapseforce required to collapse the vessel is about 14% greater than thecollapse force required to collapse the non-cellular vessel.

Clause 53. The vessel of any preceding clause, wherein a mass of thevessel is about 40 grams and a mass of the non-cellular vessel is about44 grams.

Clause 54. The vessel of any preceding clause, wherein the collapseforce required to collapse the vessel is about 2% greater than thecollapse force required to collapse the non-cellular vessel.

Clause 55. The vessel of any preceding clause, wherein a mass of thevessel is about 5% to about 15% smaller than a mass of the non-cellularvessel is about 35 grams.

Clause 56. The vessel of any preceding clause, wherein the collapseforce required to collapse the vessel is about 1% to about 25% greaterthan a collapse force required to collapse the non-cellular vessel.

Clause 57. The vessel of any preceding clause, wherein the middlecellular polymeric material comprises high density polyethylene.

Clause 58. The vessel of any preceding clause, wherein the middlecellular polymeric material is one of linear low density polyethylene,low density polyethylene, an ethylene copolymer, copolymerpolypropylene, polypropylene, polystyrene, nylon, polycarbonate,polyester, copolyester, poly phenylene sulfide, poly phenylene oxide, arandom copolymer, a block copolymer, an impact copolymer, homopolymerpolypropylene, polylactic acid, polyethylene terephthalate,crystallizable polyethylene terephthalate, styrene acrilynitrile, andcombinations thereof.

Clause 59. The vessel of any preceding clause, wherein the middlecellular polymeric material is linear low density polyethylene.

Clause 60. The vessel of any preceding clause, wherein the middlecellular polymeric material is low density polyethylene.

Clause 61. The vessel of any preceding clause, wherein the middlecellular polymeric material is an ethylene copolymer.

Clause 62. The vessel of any preceding clause, wherein the ethylenecopolymer is TOPAS®.

Clause 63. The vessel of any preceding clause, wherein the middlecellular polymeric material is copolymer polypropylene.

Clause 64. The vessel of any preceding clause, wherein the middlecellular polymeric material is polypropylene.

Clause 65. The vessel of any preceding clause, wherein the middlecellular polymeric material is polystyrene.

Clause 66. The vessel of any preceding clause, wherein the middlecellular polymeric material is nylon.

Clause 67. The vessel of any preceding clause, wherein the nylon isnylon 6/6.

Clause 68. The vessel of any preceding clause, wherein the nylon isnylon 6.

Clause 69. The vessel of any preceding clause, wherein the middlecellular polymeric material is polycarbonate.

Clause 70. The vessel of any preceding clause, wherein the middlecellular polymeric material is polyester.

Clause 71. The vessel of any preceding clause, wherein the middlecellular polymeric material is copolyester.

Clause 72. The vessel of any preceding clause, wherein the middlecellular polymeric material is poly phenylene sulfide.

Clause 73. The vessel of any preceding clause, wherein the middlecellular polymeric material is poly phenylene oxide.

Clause 74. The vessel of any preceding clause, wherein the middlecellular polymeric material is a random copolymer.

Clause 75. The vessel of any preceding clause, wherein the middlecellular polymeric material is a block copolymer.

Clause 76. The vessel of any preceding clause, wherein the middlecellular polymeric material is an impact copolymer.

Clause 77. The vessel of any preceding clause, wherein the middlecellular polymeric material is homopolymer polypropylene.

Clause 78. The vessel of any preceding clause, wherein the middlecellular polymeric material is polylactic acid.

Clause 79. The vessel of any preceding clause, wherein the middlecellular polymeric material is polyethylene terephthalate.

Clause 80. The vessel of any preceding clause, wherein the polyethyleneterephthalate is crystallizable polyethylene terephthalate.

Clause 81. The vessel of any preceding clause, wherein the middlecellular polymeric material is and styrene acrilynitrile.

Clause 82. The vessel of any preceding clause, wherein the middlecellular polymeric material is poly methyl methacrylate.

Clause 83. The vessel of any preceding clause, wherein the middlecellular polymeric material is polyvinyl chloride.

Clause 84. The vessel of any preceding clause, wherein the middlecellular polymeric material is acrylonitrile butadiene styrene.

Clause 85. The vessel of any preceding clause, wherein the middlecellular polymeric material is polyacrylonitrile.

Clause 86. The vessel of any preceding clause, wherein the middlecellular polymeric material is polyamide.

The invention claimed is:
 1. A vessel comprising a floor and a seamlessside wall coupled to the floor and arranged to extend upwardly fromground underlying the floor and to cooperate with the floor to define aninterior product-storage region therebetween, wherein the floor and theseamless side wall cooperate to form a monolithic element comprising aninner polymeric layer forming a boundary of the interior product-storageregion, an outer polymeric layer arranged to lie in spaced-apartrelation to the inner polymeric layer to define a core chambertherebetween, and a middle cellular non-aromatic polymeric materiallocated in the core chamber to lie between the outer polymeric layer andthe inner polymeric layer so as to contact the inner polymeric layer andthe outer polymeric layer, and wherein the inner polymeric layer, theouter polymeric layer, and the middle cellular non-aromatic polymericmaterial cooperate to provide means for maximizing a compressivestrength of the vessel as tested by top-load testing and a shearstrength of the vessel as tested by side-wall rigidity testing whileminimizing a weight of the vessel.
 2. The vessel of claim 1, wherein themiddle cellular non-aromatic polymeric material comprises high-densitypolyethylene.
 3. The vessel of claim 2, wherein the density of themiddle cellular non-aromatic polymeric material is in a range of about0.1 g/cm³ to about 0.185 g/cm³.
 4. The vessel of claim 1, wherein thevessel has an average density in a density range of about 0.51 g/cm³ toabout 0.91 g/cm³.
 5. The vessel of claim 4, wherein the compressionstrength of the vessel is greater than a compression strength of acontrol vessel having a mass about the same as a mass of the vessel anda shape about the same as a shape of the vessel.
 6. The vessel of claim5, wherein the compression strength of the vessel is about 5% to about30% greater than the compression strength of the control vessel.
 7. Thevessel of claim 4, wherein the shear strength of the vessel is greaterthan a shear strength of a control vessel having a mass about the sameas a mass of the vessel and a shape about the same as a shape of thevessel.
 8. The vessel of claim 7, wherein the compression strength ofthe vessel is about 3% to about 30% greater the compression strength ofthe control vessel.
 9. The vessel of claim 4, wherein the averagedensity is about 0.91 g/cm³.
 10. The vessel of claim 9, wherein thecompression strength of the vessel is about 9% greater than acompression strength of a control vessel having a mass about the same asa mass of the vessel a shape about the same as a shape of the vessel.11. The vessel of claim 10, wherein the shear strength of the vessel isabout 4% greater than a shear strength of a control vessel having a massabout the same as a mass of the vessel and a shape about the same as ashape of the vessel.
 12. The vessel of claim 4, wherein the densityrange is about 0.6 g/cm³ to about 0.8 g/cm³.
 13. The vessel of claim 12,wherein the average density is about 0.61 g/cm³.
 14. The vessel of claim13, wherein the compression strength of the vessel is about 15% greaterthan a compression strength of a control vessel having a mass about thesame as a mass of the vessel a shape about the same as a shape of thevessel.
 15. The vessel of claim 14, wherein the shear strength of thevessel is about 15% greater than a shear strength of a control vesselhaving a mass about the same as a mass of the vessel and a shape aboutthe same as a shape of the vessel.
 16. The vessel of claim 12, whereinthe average density is about 0.71 g/cm³.
 17. The vessel of claim 16,wherein the compression strength of the vessel is about 26% greater thana compression strength of a control vessel having a mass about the sameas a mass of the vessel and a shape about the same as a shape of thevessel.
 18. The vessel of claim 17, wherein the shear strength of thevessel is about 24% greater than a shear strength of a control vesselhaving a mass about the same as a mass of the vessel and a shape aboutthe same as a shape of the vessel.
 19. The vessel of claim 18, whereinthe vessel has a mass of about 56 grams.
 20. The vessel of claim 16,wherein the shear strength of the vessel is about 24% greater than ashear strength of a control vessel having a mass about the same as amass of the vessel and a shape about the same as a shape of the vessel.21. A vessel comprising a floor and a seamless side wall coupled to thefloor and arranged to extend upwardly from ground underlying the floorand to cooperate with the floor to define an interior product-storageregion therebetween, wherein the floor and the seamless side wallcooperate to form a monolithic element comprising an inner polymericlayer forming a boundary of the interior product-storage region, anouter polymeric layer arranged to lie in spaced-apart relation to theinner polymeric layer to define a core chamber therebetween, and amiddle cellular polymeric material located in the core chamber to liebetween the outer polymeric layer and the inner polymeric layer so as tocontact the inner polymeric layer and the outer polymeric layer, andwherein the inner polymeric layer, the outer polymeric layer, and themiddle cellular non-aromatic polymeric material cooperate to maximizeresistance to a collapse force while minimizing a weight of the vessel.22. The vessel of claim 21, wherein the middle cellular polymericmaterial comprises high density polyethylene.
 23. The vessel of claim21, wherein the middle cellular polymeric material is one of linear lowdensity polyethylene, low density polyethylene, an ethylene copolymer,copolymer polypropylene, polypropylene, polystyrene, nylon,polycarbonate, polyester, copolyester, poly phenylene sulfide, polyphenylene oxide, a random copolymer, a block copolymer, an impactcopolymer, homopolymer polypropylene, polylactic acid, polyethyleneterephthalate, crystallizable polyethylene terephthalate, styreneacrilynitrile, poly methyl methacrylate, polyvinyl chloride,acrylonitrile butadiene styrene, polyacrylonitrile, polyamide, andcombinations thereof.
 24. The vessel of claim 21, wherein the density ofthe middle cellular polymeric material is in a range of about 0.1 g/cm³to about 0.185 g/cm³.
 25. The vessel of claim 24, wherein the collapseforce required to collapse the vessel is greater than a collapse forcerequired to collapse a non-cellular vessel having a shape about the sameas a shape of the vessel.
 26. The vessel of claim 25, wherein a mass ofthe vessel is about equal to a mass of the non-cellular vessel.
 27. Thevessel of claim 26, wherein the collapse force required to collapse thevessel is about 55% to about 65% greater than the collapse forcerequired to collapse the non-cellular vessel.
 28. The vessel of claim27, wherein the collapse force required to collapse the vessel is about58% greater than the collapse force required to collapse thenon-cellular vessel.
 29. The vessel of claim 28, wherein the mass isabout 35 grams.
 30. The vessel of claim 27, wherein the collapse forcerequired to collapse the vessel is about 61% greater than the collapseforce required to collapse the non-cellular vessel.
 31. The vessel ofclaim 30, wherein the mass is about 40 grams.
 32. The vessel of claim25, wherein a mass of the vessel is less than a mass of the non-cellularvessel.
 33. The vessel of claim 32, wherein the collapse force requiredto collapse the vessel is about 1% to about 25% greater than a collapseforce required to collapse the non-cellular vessel.
 34. The vessel ofclaim 33, wherein a mass of the vessel is about 32 grams and a mass ofthe non-cellular vessel is about 35 grams.
 35. The vessel of claim 34,wherein the collapse force required to collapse the vessel is about 23%greater than the collapse force required to collapse the non-cellularvessel.
 36. The vessel of claim 21, wherein a mass of the vessel isabout 35 grams and a mass of the non-cellular vessel is about 40 grams.37. The vessel of claim 36, wherein the collapse force required tocollapse the vessel is about 14% greater than the collapse forcerequired to collapse the non-cellular vessel.
 38. The vessel of claim21, wherein a mass of the vessel is about 40 grams and a mass of thenon-cellular vessel is about 44 grams.
 39. The vessel of claim 38,wherein the collapse force required to collapse the vessel is about 2%greater than the collapse force required to collapse the non-cellularvessel.
 40. The vessel of claim 21, wherein a mass of the vessel isabout 5% to about 15% smaller than a mass of the non-cellular vessel isabout 35 grams.
 41. The vessel of claim 40, wherein the collapse forcerequired to collapse the vessel is about 1% to about 25% greater than acollapse force required to collapse the non-cellular vessel.